Method of making molded flat sound-records.



Elm 867,975. DP-ATENTED OCT. 15, 1907.

W.'H. HOYT. METHOD OF MAKING MOLDED FLAT SOUND RECORDS.

urmonzon rum) 00117. 1906.

INVENTOI? 111$; vwm

/ 4. 3 Y Arromvsrs WITNESS WI LLIAM l-[EIlM' HOYT, 01- WYOMING, SEW JERSEY.

METHOD OF MAKING MOLDED FLAT SOUND RECORDS.

Specification of Letters Patent.

Patented Oct. 15, 1907.

Application filed October 17,1906-r Serial No. 339,330-

I To all who": it may concern:

Be it known that'l, \YiLLIAu HELM How, a citizen of the .United States. and a resident of Wyoming, county of Essex, and State of New Jersey, have invented' certain new and useful Improvements in Methods of Making Molded Flat Sound-Records, of which the following is a specification. 7

My invention relates to methods for making molded articles and particularly molded fiat sound records for talking machines and has for its object to cheapen the -cost of ma nufacture of such articles withoutimpairing the efficiency or wearing qualities thereof.

Reference is to be had to the accompanying drawing in which Figure l is a vertical section illustrating one of the steps of my method; Fig. 2 is a. vertical section showing the mold employed, at a subsequent stage of the process, the section being taken on line 2-2 of Fig.3;

Fig. 3 is plan view. of such mold; and Fig. 4 is a .cross-section of part of a record made according to my invention.

In manufacturing records or other articles according to my improved method I first take a lot of stock which -I will call A, and which is composed of very cheap material such as refined. asphaltum or resinous material and form it into disks 1 of the required size and thickness in any convenient; manner, as for instance by means of-a suitable machine. Thenl take a second stock which I will call B and which is composed of high-grade material and grind it into a very fine powder. As an example of a material suitable for this stockB, I will describe a body obtained by mixing and heating so a'sto cause them to form a coherent mass, the following ingredients;

' Shellac 40 parts (by weight),

Shoddy :6 Asbestos 5 Pigment 4 Clays These clays may be a mixture of barytes, china clay, pipe clay, etc. Thcreupon I take a piece 2 of muslin or canvas or other suitable material and place it on a heating table 3 which may be of anylcustomary construction. Adisk 1 made of the stock A is now taken ,and one surface of said disk is covered with the powderediB stock, as indicated at- 4. lost enough powdered B stock is used to cover the surface of the disk evenly. I now place the disk made ofA stock and sprinkled with B stock on top of the muslin 2 on the table 3 (heated by a gas hunter 3 or otherwise) with the powdered side upward-and cover it with-a. pan 5 or other suitable article to confine the heat so that the disk I quickly becomes soft or plastic. When the disk hasbecpme sufiicientlyplasticthe powdered B While in this state, I remove the diskfrom the heating stock and the disk of A'stock become one coherent mass.

table-by means of the muslin or other iabric',a-nd place it on the face of a matrix 6 in a mold I with the surface of the disk to which the powdered B stock was applied of two members, the lower one of w l iich 8 'is of the same size as the-disk, while the upper'member Q is much larger, being guided on pins 7 and 7. The arrangement is duplicated. above the plate 9. in reverse order the corresponding parts being designated by-the same reference numerals with the addition of the index Pressure' is then applied and maintained until the record disks-have become 'cold after which said disks are removed and are'ready for use. The entiremoltl, that is, both matrices 6 and 6" as well as the intermediate plate '9 and topplate 7"- are heated'before the molding operation. I prefer to place some loose material such as a hot soft lump (10 or 10) of A stock or other plastic material on the central portion of the disk 1 before the molding pressure is applied, so that this lump may spread toward the periphery and in so doing drive out the air from between the plate 8 or 8 and the disk. In the finished article (Fi 4') this material forms a coating 11 on the side of the record disk 1 eppo-- subjected to wear is thus composed of high-grade mate1'ial, while the remainder of the record is made of comparatively cheap stock. This results in a record with the same qualities as if the entire disk were made of the best materials, while the'cost 'of making such record is reduced to a. minimum.

flwo records are made simultaneously with the arrangementdescribed, but when it is' desired to make only op retiord, the parts above the plate 9 are omitted, and pressure is applied to said plate directly.

Old or worn records of the present kind may be used as equivalents of the disks 1 made of A stock, such old records being sprinkled with Bstock and treated as above described, thus resulting in a new and better record. This also effects a big saving as by treating old records in this manner the necessity for making disks of A stock 'is avoided. In either case the'disks (whether old records or especially made) form a. foundation for the coating of powdered B stock.

Various modifications may be made without depart-- ing from the nature of myinvention as defined in the claims.

It will be understood that the relativesizes of varrious parts, and particularly those ofthe'sound record layers, have been considerably exaggerated in the drawings; for the sake of clezu'ness I claim 1. The herein described method of making flat molded articles, which consists in applying to the upper surface of a flat foundation which becomes plastic under the influence of heat, a layer of powdered material having like properties, heating the foundation and said layer to caiise them to unite, then placing on the.oth er surface oi' the foundation, near the'center, some loose material of the same character, and' applying heat and pressure to cause said loose material to expand and expel the air, and the entire article to be molded. 

